The people complaining about these things are literally self-identifying themselves as the bad guy. We're not making you use these words. We're not making you self-identify as the bad guy. We didn't put the rake there, but they're proudly stomping on it anyways.
Take for example the aforementioned grandparent: It's justice to redistribute wealth from those above some arbitrary line to those below (grandparent is presumably below it). That's only justice for him, it's bullshit to everyone else.
And you know what happens when differing senses of justice collide? Possibly made worse by fervor? Very Unpleasant Things(tm).
This is why we use legal justice rather than social justice: There is one and only one standard of justice that we all agree to accept after much deliberation.
Ergo, arguing justice (FSVO justice) for society.
As such, I am of the position that this is one of those rare situations where the term "social justice warrior" is meaningful and accurate.